An insider's view on the big bang

ASTRONOMER Chris Impey isn't quite sure whether he'd bet more than the tip of his little finger on the big bang theory being right. He reckons his whole forearm would be a lot to put up for a bet on science, with all its uncertainties. Losing the tip of his pinkie seems about right: he would at least be able to wear the disfigurement as an astronomer's badge of honour, a mark of his trust in the four independent strands of evidence that support our best theory of how the universe began.

Having dispensed with How it Ends in his impressive last book, Impey has now turned his attention to the start of everything. It is no less of a treat; somehow he renders the universe tangible to the human brain, never forgetting to relate cosmic concepts to our everyday scales of experience. Riffing on the vastness of the solar system, he points out how long it takes signals to travel to Mars and back, and how that affects the speed at which NASA engineers can move their robot explorers across the Red Planet's surface. "In a Mars day, the rovers would barely cross your living room," he says, neatly conveying the grinding tedium that is inseparable from the extraordinary achievements of our space programmes.

Impey is in a class of his own when it comes to guiding the reader through the infinite reaches of the universe. He is a masterly exponent of comparison and metaphor; the galaxies, he says, are butterflies caught mid-flight, "arranged on black felt all around us, ready for our inspection".

He wears his insider's knowledge lightly and is generous towards those who approach the universe and existence from a religious viewpoint. He sometimes travels to Tibet to teach cosmology to Buddhist monks. And he counts the Jesuit priest-astronomers who make annual pilgrimages to Arizona in order to use a telescope in the Pinaleño mountains as "valued friends and colleagues" - though he admits he hasn't yet worked out whether it is OK to wear swimming trunks while watching them celebrate mass.

That's not the only unknown this Arizona-based astronomer faces, though. Replete with dark matter and dark energy, the universe is "mocking us with its secrets". We are, he says, "a young species, and our science is also immature". Impey is fine with astronomers not yet having all the answers, and many are painted here as flawed characters acting as strangely as humans often do.

Impey comes across as very human himself: this is not just a book about the history of the cosmos, it is a compelling insight into what it is to be an astronomer grappling with the fundamental questions of existence.

Book InformationHow it Began: A time-traveler's guide to the universeby Chris Impey
Published by: W. W. Norton
£17.99/$27.95

...to relate cosmic concepts to our everyday scales of experience...the phrase in sentence says it all. Should a universe have a begining and end at all? Why we can't take our cue from Mossbauer strip or just simply from a circle, which may not have beginning and end. One accepts if there is a beginning then it has to have an end. One ponder if it is so. But, neither may be there